Chemical workers exposed to chronic, EPA-regulated levels of vinyl chloride (VC), an established human carcinogen, and acrylonitrile (AN), a carcinogen-suspect, have shown higher than expected occurrence of liver abnormalities. However, their etiology has remained elusive due to a lack of molecular markers for exposure. Our interest is in molecular dosimetry of VC and AN metabolites as human exposure markers. Despite the current advanced state of GC-MS analytical technique, it is not practical method for the task at hand. The recently demonstrated methodology of making monoclonal antibodies (MAb) to chemicals provides a new means of assessing exposure in a more sensitive and specific manner. Our aims are: (1) Synthesize immunogens of VC and AN. In respect to VC, whose putative metabolites chloroethylene oxide (CEO) and chloroacetaldehyde (CAA) are well known to react with DNA, the crucial DNA adducts responsible for the genotoxicity of CEO and CAA are detection targets. On the other hand, AN and its epoxide metabolite ANO are unreactive towards DNA. Their major reaction is with glutathione (GSH), and hence the GS-conjugates are prime targets. In this seed project, four of these metabolites will be fashioned into synthetic antigens. (2)Raise monoclonal antibodies to the above synthetic antigens in BALB/c mice. ELISA will be used to screen for anti- hapten antibodies, optimizing immunization parameters for their presence in antiserum. The spleen cells of immunized mouse will be converted to hybridoma to produce MAb. Presently, we have produced a MAb to the GS-AN conjugate. (3) Interpret the immunoassays of metabolites for the purpose of VC and AN carcinogenesis/toxicology study. A dose-response curve for each MAb-antigen pair will be established by assaying blood supplemented with known amounts of specific metabolites. An NIH 3T3 transfection assay of c-Ha-ras-1 oncogene, modified by CEO or CAA in vitro, will be conducted to ascertain the relationship of these DNA adducts to carcinogenesis. Preliminary data have shown that CAA activates c-ras to a transforming oncogene by a codon-12 modification of quanine, hence supporting our choice of the CAA-DNA adduct. In summary, this grant will support the production of 4 MAb and laboratory evaluation of their applicability in vinyl carcinogenesis study.